The invention is based on a manual planing machine, a planer shaft, a planer knife and a spacer strip respectively.
DE-OS 91 52 65 discloses a planing machine with a cutter head or planer shaft whose elongated planer knives extend over the width of the planer shaft and can be clamped by clamping wedges which are carried by the planer shaft and are actuated by centrifugal force. The known planing machine is suitable only for clamping large-volume planer knives. The considerably smaller and thinner carbide mini reversible tips, e.g., in the standard size of 1.1 mm thickness and 5.5 mm height, cannot be clamped in any definite position in the known planing machines because they have a volume and mass roughly ten times smaller than the large-volume planer knives. The large-volume planer knife cannot be economically produced from carbide due to its large dimensions because the cost of carbide is very high, so that only high-speed steel planer knives of lesser stability and quality are considered for the known planers.
EP 01 17 991 discloses a planing machine with a planer shaft formed of profile disks, wherein a clamping wedge actuated by centrifugal force is arranged in the longitudinal groove of the planer shaft. This planer shaft is also not suitable for receiving mini reversible tips, but only for conventional high-power high-speed steel knives with an approximate thickness of 3 mm and a height of 11.5 mm. These would also be just as uneconomical as carbide knives in terms of construction.
Patent FR 2 477 460 discloses a clamping device at a planer shaft for large-volume rusticating planer knives with a corrugated cutter which, alternatively, can also receive dual-cutting straight mini reversible tips. For this purpose, a shavings or chip rejecting part is inserted in a longitudinal groove of the planer shaft, wherein this chip rejecting part is supported at the groove flank located in front of the planer knife in the direction of rotation and clamps the planer knife against the other groove flank. The chip rejecter has, on its side facing radially outward, a corrugated profile corresponding to the large-volume rusticating cutter profile.
If a mini reversible tip is to be clamped instead of the rusticating planer knife, clamping cannot be carried out exclusively by the clamping wedge, but rather an additional clamping body is needed which clamps itself--and, in so doing, also the mini reversible tip--between the clamping wedge and the outer groove flank.
Clamping wedges of the type mentioned above are complicated to produce and are accordingly expensive. Further, the rusticating knife clamping wedge must be exchanged with standard clamping wedges with a straight chip rejecting part when using straight planer knives because of the corrugated chip rejecting part. This complicates the exchanging of planer knives and, moreover, requires special storage for the different clamping wedges.
The corrugated chip rejecting part is necessary for limiting chip thickness because the maximum chip thickness in rusticating planer knives is appreciably thicker than in straight planer knives. This is because the thinnest chips generated by the corrugation troughs of the cutter must also still have a sufficient thickness for high surface quality. Therefore, the minimum chip thickness in rusticating knives is adapted to the minimum chip thickness of straight planer knives, wherein the maximum chip thickness must be about one millimeter thicker than the minimum chip thickness for the rusticated texture to be visually effective.
Since the risk of a back-kick increases with the chip thickness when working with the planer, the chip thickness is limited to a maximum 1.1 mm.